/* ===================================
   Hot Water Tank Monitoring Dashboard
   Responsive CSS Styling
   =================================== */

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette */
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --success-color: #27ae60;
    --warning-color: #f39c12;
    --danger-color: #e74c3c;
    --light-bg: #f5f5f5;
    --white: #ffffff;
    --text-primary: #333333;
    --text-secondary: #666666;
    --border-color: #e0e0e0;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.15);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Helvetica Neue', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--light-bg);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ===================================
   Header Styling
   =================================== */

.header {
    background: linear-gradient(135deg, var(--primary-color) 0%, #34495e 100%);
    color: var(--white);
    padding: var(--spacing-sm) var(--spacing-lg);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.header-title {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.5px;
}

.auth-container {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.auth-status {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.auth-status-text {
    font-size: 0.9rem;
    opacity: 0.9;
}

.auth-button {
    background-color: var(--secondary-color);
    color: var(--white);
    border: none;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.auth-button:hover {
    background-color: #2980b9;
}

.auth-button:active {
    transform: scale(0.98);
}

/* ===================================
   Main Content Layout
   =================================== */

.main-content {
    flex: 1;
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: var(--spacing-lg);
}

.section {
    background: var(--white);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    transition: box-shadow var(--transition-normal);
}

.section:hover {
    box-shadow: var(--shadow-md);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.section-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
}

/* ===================================
   Tank Visualization Styling
   =================================== */

.tank-section {
    min-height: 500px;
}

.status-indicator {
    display: flex;
    align-items: center;
}

.status-badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-lg);
    font-size: 0.85rem;
    font-weight: 500;
    background-color: var(--warning-color);
    color: var(--white);
}

.status-badge.connected {
    background-color: var(--success-color);
}

.status-badge.disconnected {
    background-color: var(--danger-color);
}

.tank-container {
    min-height: 400px;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: var(--spacing-lg);
    background: linear-gradient(to bottom, #f8f9fa 0%, #e9ecef 100%);
    border-radius: var(--radius-md);
    border: 2px solid var(--border-color);
}

.tank-svg {
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

.sensor-marker {
    transition: all var(--transition-fast);
    cursor: pointer;
}

.sensor-marker:hover {
    r: 10;
    filter: drop-shadow(0 0 4px rgba(255, 152, 0, 0.8));
}

.temp-display {
    transition: fill var(--transition-fast);
}

.timestamp-display {
    font-style: italic;
}

.stale-warning {
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.7;
    }
}

.placeholder-message {
    color: var(--text-secondary);
    font-size: 1rem;
    text-align: center;
}

.tank-info {
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
}

.last-reading {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

#last-reading-time {
    font-weight: 600;
    color: var(--text-primary);
}

/* ===================================
   Chart Container Styling
   =================================== */

.chart-section {
    min-height: 450px;
}

.chart-controls {
    display: flex;
    gap: var(--spacing-sm);
}

.time-range-select {
    padding: var(--spacing-xs) var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    background-color: var(--white);
    color: var(--text-primary);
    font-size: 0.9rem;
    cursor: pointer;
    transition: border-color var(--transition-fast);
}

.time-range-select:hover {
    border-color: var(--secondary-color);
}

.time-range-select:focus {
    outline: none;
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

.chart-container {
    position: relative;
    height: 400px;
    margin-top: var(--spacing-md);
}

#temp-chart {
    max-width: 100%;
    max-height: 100%;
}

/* ===================================
   Error Message Styling
   =================================== */

.error-section {
    background: linear-gradient(135deg, #fee 0%, #fdd 100%);
    border: 2px solid var(--danger-color);
    animation: slideDown var(--transition-normal);
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.error-container {
    display: flex;
    gap: var(--spacing-md);
    align-items: flex-start;
}

.error-icon {
    font-size: 2rem;
    flex-shrink: 0;
}

.error-content {
    flex: 1;
}

.error-title {
    color: var(--danger-color);
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.error-message {
    color: #c33;
    margin-bottom: var(--spacing-md);
    line-height: 1.5;
}

.error-actions {
    display: flex;
    gap: var(--spacing-xs);
    flex-wrap: wrap;
}

.error-retry-button,
.error-dismiss-button {
    padding: var(--spacing-xs) var(--spacing-md);
    border: none;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.error-retry-button {
    background-color: var(--danger-color);
    color: var(--white);
}

.error-retry-button:hover {
    background-color: #c0392b;
}

.error-retry-button:active {
    transform: scale(0.98);
}

.error-dismiss-button {
    background-color: transparent;
    color: var(--danger-color);
    border: 1px solid var(--danger-color);
}

.error-dismiss-button:hover {
    background-color: rgba(231, 76, 60, 0.1);
}

.error-dismiss-button:active {
    transform: scale(0.98);
}

/* ===================================
   Offline Indicator Styling
   =================================== */

.offline-indicator {
    position: fixed;
    top: 80px;
    right: var(--spacing-lg);
    background: linear-gradient(135deg, #ff9800 0%, #f57c00 100%);
    color: var(--white);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    animation: slideInRight var(--transition-normal);
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(100%);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.offline-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.offline-icon {
    font-size: 1.2rem;
}

.offline-text {
    font-weight: 500;
    font-size: 0.9rem;
}

/* ===================================
   Footer Styling
   =================================== */

.footer {
    background-color: var(--white);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-md) var(--spacing-lg);
    margin-top: auto;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.footer-text,
.footer-info {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.last-update-time,
#device-id {
    font-weight: 600;
    color: var(--text-primary);
}

/* ===================================
   Responsive Design - Mobile
   =================================== */

@media (max-width: 768px) {
    .header {
        padding: var(--spacing-sm);
    }
    
    .header-content {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .header-title {
        font-size: 1.25rem;
    }
    
    .main-content {
        padding: var(--spacing-sm);
    }
    
    .section {
        padding: var(--spacing-md);
        margin-bottom: var(--spacing-md);
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .section-title {
        font-size: 1.1rem;
    }
    
    .tank-container {
        min-height: 300px;
        padding: var(--spacing-md);
    }
    
    .chart-container {
        height: 300px;
    }
    
    .error-container {
        flex-direction: column;
    }
    
    .offline-indicator {
        top: 60px;
        right: var(--spacing-sm);
        left: var(--spacing-sm);
    }
    
    .footer-content {
        flex-direction: column;
        align-items: flex-start;
        text-align: left;
    }
}

/* ===================================
   Responsive Design - Tablet
   =================================== */

@media (min-width: 769px) and (max-width: 1024px) {
    .main-content {
        padding: var(--spacing-md);
    }
    
    .header-title {
        font-size: 1.35rem;
    }
}

/* ===================================
   Utility Classes
   =================================== */

.hidden {
    display: none !important;
}

.loading {
    opacity: 0.6;
    pointer-events: none;
}

.fade-in {
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* ===================================
   Print Styles
   =================================== */

@media print {
    .header,
    .footer,
    .auth-container,
    .error-section {
        display: none;
    }
    
    .section {
        box-shadow: none;
        border: 1px solid var(--border-color);
        page-break-inside: avoid;
    }
}

/* ===================================
   Authentication Loading Screen
   =================================== */

.auth-loading {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.auth-loading-content {
    text-align: center;
    color: white;
}

.auth-loading-content p {
    margin-top: 20px;
    font-size: 16px;
    font-weight: 500;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin: 0 auto;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Hide main app by default until authenticated */
#main-app {
    display: none;
}

#main-app.authenticated {
    display: block;
}